Heat and cold have both been used to effectively treat afflicted patients. Directly applying liquid to afflicted cells is also well known. Cold has often been used as a localized treatment, while heat has been, and is currently used as both a localized and total body treatment. Using heat to treat a localized afflicted area of an afflicted patient is most relevant to the present invention.
The search continues for ways to effectively treat wounds, tumors and similar disorders while minimizing adverse collateral effects. For example, assignee has been a leader in treating open wounds through a process known as Vacuum Assisted Closure™, (“V.A.C.®”). In a similar vein, localized thermotherapy, primarily localized hyperthermia, has also shown promise as a treatment modality which is capable of producing beneficial therapeutic effects without significant adverse collateral effects for certain conditions. However, the localized hyperthermic treatment modalities in the prior art, all suffer from serious drawbacks, limitations, or side effects.
Research has demonstrated that heating cancerous, or other abnormal cells to over about 42° Celsius (“C.”) can kill the abnormal cells, while causing little damage to the surrounding normal cells. This treatment is temperature sensitive. Heating the cancer cells, for example, to a temperature between nominal body temperature, 37° C. and approximately 41° C. or greater can seriously damage them. To maximize patient safety, this hyperthermia treatment must be localized.
The variety of available heat transfer methods for localized thermotherapy is limited. Heat is transferred in three ways, radiation, convection, or conduction. The heat transfer medium creating the localized hyperthermia can be either heated in situ or be heated exogenously, before being placed upon the patient. The medium can either be placed in direct contact with the afflicted cells or, transfer heat to the afflicted cells through an intermediary.
Localized hyperthermia therapy is presently used in treating prostate afflictions, breast cancer, and other afflictions. This modality involves placing implants about the afflicted patient's afflicted cells, and then heating the implants by radiating EMF or ultrasonic energy thereto. The heat from the implants then migrates into the afflicted tissue, via conduction, thereby raising the temperature of the afflicted cells. Several issued patents demonstrate variations of this technique. Issues relating to possible adverse affects of exposure to both radiation, and radiated energy abound. However, as most sufferers of prostate cancer are older men who are past the age of fathering children, and female breasts are relatively remote from the female reproductive organs, the possible long-term adverse collateral effects of using such radiant energy treatments are minimized.
Applicant has discovered various patents that employ and exemplify other energy transfer methods and media in creating localized hyperthermias. The first of these patents, Guibert, U.S. Pat. No. 4,595,008, issued Jun. 17, 1986, may be summarized as follows:
“ . . . air heated to a temperature well above normal body temperature is projected as a high velocity stream in a pulsatory wave pattern toward a localized skin area overlying a problem region, thereby subjecting this area to high-velocity heated air pulses separated by lower air temperature, relatively static intervals.
“The pulsatory wave pattern is created by apparatus, which operates in a periodic interruption mode, in a cyclical stepping mode or in a cyclical sweeping mode, depending on the nature of the instrument and its intended applications.
“As a consequence of the pulsatory wave pattern, heat transfer takes place through the body tissue toward the problem region during the intervals between the pulses, this inward transfer acting to reduce the temperature at the skin surface to a degree preventing an undue rise thereof. While during the pulse periods the temperature of the hot air at the skin surface is much higher than body temperature, the duration of each pulse is relatively short and insufficient to cause discomfort or injury to the patient.” Guibert Col. 2 line 61-Col. 3 line 15.
This description shows that Guibert uses a heated fluid to indirectly transfer heat to an afflicted area of a patient; the fluid, air, does not come into contact with the afflicted area. Another device that also uses a heated fluid to treat an afflicted portion of a patient's body is Shantha, U.S. Pat. No. 5,195,965 issued Mar. 23, 1993. Shantha may be summarized as follows:
“ . . . the present invention comprises an apparatus for heating the interior surfaces of a hollow organ or orifice, for example the interior surfaces of the reproductive tract of a female human being, for the treatment of viral infections and cancers. For example, the invention is useful for the treatment of Human Papilloma Virus, chlamydia, trichomonas vaginitis, vaginal yeast infections, gonococcus, rectal and anal infections, rectal and anal cancers, esophageal cancer, etc. The apparatus comprises an insertion body having a flexible outer surface and is adapted for insertion into the hollow organ or orifice, such as the female reproductive tract. The insertion body is adapted to contact and conform to the interior surfaces of the hollow organ. The apparatus also includes means for heating the outer surface of the insertion body and for maintaining a selected temperature at the outer surface.
“Preferably, the insertion body comprises an inflatable outer membrane or balloon supported about a semi-rigid support member. The inflatable balloon is adapted to contain liquid under pressure and the apparatus includes means for circulating liquid between the inflatable balloon and an external heating device. Sensor means are positioned along the outer surface of the inflatable balloon for determining the temperature of the outer surface of the balloon. Control means, responsive to the temperature of the outer surface as determined by the sensor means, are provided for controlling the external heating device so as to maintain the temperature of the outer surface at the selected temperature.
“With this construction, the inflatable balloon can be inserted into the hollow organ in an uninflated state and subsequently inflated with liquid under pressure. The liquid is then circulated and heated in the external heating device. The liquid, preferably water, is maintained at a temperature of between 40° C. and 44° C. for between 2 and 6 hours. Preferably, the water is maintained at a temperature of 41.8° C. (roughly 107.2° F.), and the inflatable body is maintained in the hollow organ for four (4) hours kills many bacteria, viruses and cancer cells. The immune system of the patient normally is stimulated by the destroyed virus cells, microbes, and cancer cells and attacks any infected or cancerous cells not destroyed by the heat. This temperature of 41.8 degree C. is low enough that healthy tissues survives relatively undamaged, owing to the lesser heat sensitivity of healthy cells as compared with infected and cancerous cells. The localized nature of the treatment, together with the relatively low temperature involved, ensures that the risk of death to the patient from an elevated body temperature is substantially zero. The rather low temperatures involved also protect the patient from much pain and discomfort during treatment.” Shantha Col. 2., line 36-Col. 3, line 22.
Various other heated liquid devices and methods of treating hollow organs or body orifices exist, and operate in the same basic manner. However, there is a need for a system and method for the creation of a localized therapeutic hyperthermia by means of a heated liquid directly contacting afflicted cells for a period of significant duration. More particularly there is a need for a device, or method of treatment, which involves, selecting a therapeutic liquid, heating the selected liquid through conduction so as to avoid EMF or ultrasonic radiation, placing a therapeutic applicator about the afflicted cells, and circulating the heated fluid through the therapeutic applicator, thereby creating a localized hyperthermia in the afflicted cells within the circumference of the applicator. Furthermore it would be beneficial to provide the use of a localized hyperthermic modality in conjunction with Vacuum Assisted Closure™, (“V.A.C.®”) of open wounds. It is towards the fulfillment of these needs that the present invention is directed.